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arXiv · 2111.09199

Doubling constants and spectral theory on graphs

Estibalitz Durand-Cartagena·Javier Soria·Pedro Tradacete
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Abstract

We study the least doubling constant among all possible doubling measures defined on a (finite or infinite) graph $G$. We show that this constant can be estimated from below by $1+ r(A_G)$, where $r(A_G)$ is the spectral radius of the adjacency matrix of $G$, and study when both quantities coincide. We also illustrate how amenability of the automorphism group of a graph can be related to finding doubling minimizers. Finally, we give a complete characterization of graphs with doubling constant smaller than 3, in the spirit of Smith graphs.

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Estibalitz Durand-Cartagena, Javier Soria, Pedro Tradacete. 2021-11-17. Doubling constants and spectral theory on graphs. https://arxiv.org/abs/2111.09199

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